Effects of chronic ethanol consumption on aortic constriction in male and female rats

This study was designed to determine if gender influences the effects of chronic ethanol intake on vasoconstrictive responsiveness. Ethanol-preferring rats were allowed ad libitum access to tap water or tap water containing 20% or 30% ethanol for 16 weeks. All of the ethanol groups consumed more daily calories than their respective controls, and female rats consumed more ethanol calories per unit body mass than their male counterparts. Following treatment, endothelium-intact and endothelium-denuded thoracic aortic rings were used to examine the contractile response to phenylephrine. Ethanol consumption did not alter vasoconstriction in endothelium-intact aortae from either gender. In contrast, males, but not females, demonstrated an ethanol-associated increase in the maximum response to phenylephrine in endothelium-denuded preparations. Aortae from male rats that consumed 20% and 30% ethanol showed an increased contractility of 37% and 85%, respectively. These data indicate that gender influences the vasoconstrictive effects elicited by chronic ethanol consumption and suggest that males may be more susceptible to the associated hypertension.